1. Field of the Invention
The present invention relates to a mechanical apparatus used to cause various expressions on the face of an animated character.
2. Description of Related Art
This invention pertains to an expressive feature mechanism used in an animated character. The goal of this invention is to achieve a full range of human-like and recognizable facial expressions. This goal has been addressed by others and has often led to the development of devices used in animated characters that have mouths, which open and close to mimic speaking or sucking. An example of such work would be U.S. Pat. No. 4,808,142 by Berliner, which has a motor driven mouth actuator to move the mouth between open and closed positions.
U.S. Pat. No 2,250,916 by Magruder uses electromagnetic coils to animate the upper and lower lip in synchrony to sound.
U.S. Pat. No. 3,841,020 by Ryan employs a complex set of levers and actuators that allow a range of facial expressions related to the motion of a doll's arms.
U.S. Pat. No. 3,828,469 by Giroud describes a mechanism having two operating rods for moving upper and lower lips.
More recently issued patents describe techniques that allow for a greater control of lip motion. For example, U.S. Pat. No. 6,352,464 by Madland et al. describes a mechanism for an animated character. The Madland Patent describes a facial control system comprising two lip chains embedded behind two lips. The lip chains are attached at either end as well as at a center portion. By positioning the movable center portion relative to the moveable ends various facial expressions can be achieved, however, the described mechanism does not allow for stretching of the lips as it occurs on human and animal faces.
Other methods such as the one described in U.S. Pat. No. 4,177,589 by Villa include a pneumatic mechanism to open and close the mouth. That method allows for a rounding of the lips but does not allow for a full range of expression such as a frown or broad smile.
Mechanisms such as U.S. Pat. No. 6,544,098 by Hampton are capable of some recognizable expressions but only with the addition of other actions such as drooping ears or closing eyes.
Other devices of possible relevance are described in the following U.S. Pat. Nos. 4,294,033; 4,805,328; 5,376,040; 6,386,942 and 6,503,123.
The current invention comprises an improved means to make animated characters with complex facial expressions in a minimal component, minimal cost, highly efficient mechanism. This mechanism improves upon the mechanism described in the previously submitted U.S. Provisional Application Ser. No. 60/381,722 and PCT/US03/15120 filed May 14, 2003 by allowing stretch of the lip member beyond the radius of the primary drive wheels. This improved design creates a more recognizable expression with the added benefit of a more compact design per breadth of smile.